You can stop hoping. The great majority of email is sent in plain text (SMTP) and as the datagrams are routed from machine to another, they're open to interception, and in fact, are routinely logged.
SSL/TLS are cryptographic extension that attempt to secure messages in a socket communication, and by extension, application layer protocols such as SMTP.
It's not even about hacking emails. Some people have legitimate access to the information and abuse this by simple snooping or eavesdropping.
Back in the early 2000s a friend of mine worked for a large consultancy in Canada and often had to work on equipment in the Bell/Sympatico (largest ISP in Canada at the time) data centers.
While he was there, he said the network techs would routinely snoop the traffic of the customers at the router level to see what web pages they were looking at, and grep'ed mailboxes on the servers looking for funny/dirty pictures or private information (credentials for porn sites were a big one)...
I'm sure this isn't a common thing, but you can bet it happens..
You can stop hoping. The great majority of email is sent in plain text (SMTP) and as the datagrams are routed from machine to another, they're open to interception, and in fact, are routinely logged.
SSL/TLS are cryptographic extension that attempt to secure messages in a socket communication, and by extension, application layer protocols such as SMTP.